sc1486aitstr Semtech Corporation, sc1486aitstr Datasheet - Page 19

• Manufacturer Part Number: sc1486aitstr
• Description: Complete Ddr1/2/3 Power Supply Controller
• Manufacturer: Semtech Corporation

Layout Guidelines (Cont.)
The layout can be considered in two parts, the control section referenced to VSSA1/2 and the power section.
Looking at the control section first, locate all components referenced to VSSA1/2 on the schematic and place
these components at the chip. Connect VSSA1 and VSSA2 using either a wide (>0.020”) trace or a copper pour if
room allows. Very little current flows in the chip ground therefore large areas of copper are not needed.
POWER MANAGEMENT
Application Information (Cont.)
2006 Semtech Corp.
PWR_SRC
1.8V
VSSA1
C17
27p
0402
45k3
0402
17k4
0402
R13
R10
VCCA1
Figure 8: ExampleVSSA Copper Pours (Left) and 0.020” Traces (Right)
R3
1M
C20
1n
0402
R1 10R
0402
Figure 7: Components Connected to VSSA1 and VSSA2
C8
1u
0603
PGD1
VCCA1
TON1
VCCA1
C21
1u
0603
5VSUS
R2 10R
27
22
24
26
23
25
28
3
1
6
7
5
4
2
0402
U1
VDDP1
PGND1
DH1
BST1
LX1
ILIM1
DL1
PGD1
EN/PSV1
VOUT1
FB1
TON1
VCCA1
VSSA1
VCCA2
SC1486A
REFOUT
PGND2
VSSA2
VDDP2
PGD2
VCCA2
REFIN
TON2
ILIM2
FB2
BST2
DH2
DL2
LX2
19
17
15
20
21
19
18
16
13
12
8
10
9
11
14
PGD2
REFOUT
TON2
VCCA2
5VRUN
C9
1u
0603
C22
1u
0603
R4
649k
0402
C23
1n
0402
R11 10R
0402
C18
1u
0603
C19
0u1
0402
R12
10k0
0402
PWR_SRC
R9 10k0
SC1486A
0402
www.semtech.com
VSSA2
1.8V
0.9V